"These conditions can be good for everyone, not just for big servers," Pliskova said during her on-court interview.?"I think we both played pretty well, and it was my best match out here, so I'm quite happy with my performance.

"First rounds can be tough because you're never playing your tennis, but by the fourth round you're always playing good opponents," she explained after the match. "She's around No.20 in the world, and we've played just once. There were a few close points where I might have won it in two sets, but it was good quality."

The two-time?semifinalist recovered from dropping the second set?to ultimately outlast the Estonian youngster, securing victory after two hours and three?minutes on Stadium 4.

Kontaveit came into the Round of 16 having won all five games played in her previous round as 2018 US Open semifinalist Anastasija Sevastova was forced to retire due to a viral illness, and won the first three games of her clash with Pliskova.

"I have to know all the top players, so I've watched her a couple of times, and we've practiced before, so I knew her game pretty well. I had a gameplan, but that doesn't always make you win; you still have to play good points.

"I think I served well and went for my shots."

Seeded No.5 after a win at the Brisbane International and a run to the Australian Open semifinals, Pliskova has enjoyed solid form to start 2019 with a revamped coaching team that includes Rennae Stubbs and Conchita Martinez - taking pointers from the latter during coaching timeouts on Tuesday. She swept the next three games to level the set and served for it in the 12th game only for Kontaveit to force a tie-break.

Pliskova wouldn't be denied in the ensuing sudden death, striking her fifth ace to earn a whopping six set points, clinching her first shortly thereafter.

Kontaveit dialed back in to start the second set, breaking once more and keeping things close even as Pliskova leveled.

"I knew she'd play well, but maybe not this well," she admitted. "She went for her shots, and she maybe doesn't always put those in, so it was just a day where she was missing less than when we played on clay."

The 23-year-old shook off?two missed break point opportunities to break serve two games later, forcing a decider with a decisive hold.

"I probably shouldn't have lost serve at 4-4, but I thought both sets were pretty open, and it was up and down from both of us. I started better in the third set, wanting to hold my serve as much as possible, and I got my chances in the end."

Pliskova kept in front to open the final set, striking a 12th?ace (finishing the match with 13)?as the contest continued on serve. The turning point came in the sixth game, as the three-time WTA Ace Leader stepped in on return, drawing Kontaveit to net with a drop shot and putting away the reply at net to break first.

Kontaveit responded with two more break chances in the following game, only for Pliskova to erase both and break serve again - this time to love - to emerge victorious.?

"I'm happy with how I fought, because I wasn't always playing great points and not everything went my way. I got frustrated by some of her good shots and it was so close, so if you lose your focus in those moments, you can lose the match quickly."

"We're good friends off the court; she represents Switzerland but she speaks Slovak, so we can speak together in Czech language. She's a nice girl, and she's on fire right now, beating so many great players in the last two, three weeks. It's going to be tough.

"She's confident now, but I think I'm playing good tennis too, and I have some weapons. I still have to play a good game, because she beat Naomi, and it was quite quick! When she's up with her game, she can be dangerous; we've practiced together, so I can be ready."